Impulse-sending mechanism.



O. F. FORSBERG. IMPULSE SENDING MECHANISM.

APPLICATION FILED JULYI9, I917- Patented Jan. 1, 1918'.

//4 yen/0r: Oscar F Forsfiwq.

'pletel UNITED i STATES PATENT OFFICE.

OSCAR F. FORSBERG, OF 'YONKERS, NEW YORK, ASSIGNOR T0 WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

IMPULSE-SENDING MECHANISM.

Specification of Letters Patent.

Patented Jan. 1, 1918.

Application filed. July 19, 1917. Serial No. 181,589.

To all whom it may concern Be it known that I, OSCAR citizen of the United States, residing at Yonkers, in the county of Westchester and State of New York, have invented certain new and useful Improvements in Impulse- Sending Mechanisms, of which the following is a full, clear, concise, and exact description.

This invention relates to impulse sending mechanisms, and more particularly to impulse transmitters for automatic and semiautomatic telephone systems.

It is the object of this invention to provide an efiicient impulse transmitter of simple construction, which is specially adapted to be set into a wall set or into an operators .keyboard so that it will be flush with the surface of the wall set or the keyboard and thereby a smooth, even surface may be procured. 1

With this object inview according to one feature of the invention, the impulse transmitting mechanism is operated by an endless chain which is movable in a single direction, and the links of which form the finger holds of the device Another feature .of this invention is a movable stoplever which controls the operation of certain contact springs. r

Other new and useful features of the invention will appear from the following description and appended claims.

Figure 1 represents a perspective side view of the impulse transmitter with the case broken away; Fig. 2 is a partial view of the stop lever and the contact springs controlled thereby; and Fig. 3 is a perspective view of the transmitter comassembled.

Re erring to the drawings, the mechanism of the transmitter is inclosed within a case 1. Two idler pulleys 2 and 3 are rotatably mounted between the side of this case, and an endless chain 4 hangs on these idlers. On the under side of the chain a rotatable sprocket 5 is mounted between the sides of the case. This sprocket serves to tighten the chain so that the upper part of the chain between the pulleys 2 and 3 presents a straight surface alon the top of the case 1. Directly beneath this straight sur- .face a stationary plate 6 is mounted and F. FORSBERG, a n

upon it the symbols 1 to 0 are marked. The finger holds of the device are the links of the chain which are directly above these symbols and are accessible through an opening in the top of the case 1. A gear wheel 7 is fastened to the sprocket 5 by rivets 8. The gear wheel 7 meshes with gear wheel 9, which in turn meshes with a pinion 10. The pinion 10 is fastened toa rotatable shaft '11 upon which any suitable governor 12 may be mounted which will serve to regulate the maximum speed at which the chain may be moved. Such a governor is described in U. S. Patent 1,155,640 issued October 5, 1915, to G. Brown. A disk 13 of insulating material is fastened to the sprocket 5 by screws 14. The slots in disk 13 through which the screws 14 extend are elongated so that'the disk may be adjusted in relation to sprocket 5. This adjustable feature is important in that it permits variation in the manufacture of the parts and also provides ready means for compensation for wear in the links of the chains, which, due to-the multiplicity of the links, may become excessive in time.

A ring .15 of conducting material is fastened to one side of the disk 13 and a ring 26'of conducting material with slots cut out around its circumference is fastened to the other side of the disk 13 by rivets 16. These rivets also serve to electrically connect the two rings 15 and 26 together. Two-contact springs 17 and 18 are insulatedly mounted on the side of the case 1. Spring 17 is arranged to alternately engage the ring 26 and the disk 13 as the sprocket is rotated. This is due to the slots which are cut in the ring 26. Since the ring 15 does not have any slot therein the contact spring 18 is in engagement therewith at all times. Therefore, it will be seen that as the chain is moved toward the front of the device or to the right (as shown in the drawings) a circuit through contact springs 17 and 18 will is fastened to the stop 20 and the other end of which is fastened to the case. The lower end of the stop 20 carries a lug 22 of insulating material. This lug engages a contact spring 23 which is normally in engagement with contact spring 24. When the lever is operated by the finger of the user at the end of the stroke when a series of impulses is being sent, the lug 22 moves the contact spring 23 out of engagement with contact spring 2etand moves it into engagement with contact 25. A purpose for this operation at the end of the series of impulses is described in a copending application of A. B.

Sperry, Serial No. 182,967, filed July 26,

1917. The stop 20 is moved back to its normal position by spring 21, as soon as the user removes his finger from the stop. The chain, however, remains in the position to which it has been moved, as also does the sprocket 5 and the disk 13.

The top part of the case 1 between the finger stop lever 20 and the front end of the case 1 is bent so as to form an arch. It is obvious from the drawing that the users finger will engage this arch as it moves the chain toward the front of the device and that the finger will be slipped out of engagement with the selected link when it engages this arched portion.

What is claimed is:

1. In an impulse sender, the combination with an impulse transmitting mechanism having no definite normal position, of an endless chain movable in a single direction for operating said mechanism. to transmit impulses.

2. In an impulse sender, the combination with an impulse transmitting mechanism, of an endless chain movable in a single direction for operating said mechanism to transmit impulses, the links of said chain being arranged to serve as finger holds for said sender.

3. In an impulse sender, the combination with a rotatable sprocket and an impulse wheel fastened to said sprocket and adjustable in relation thereto, of an endless chain movable in a single direction for engaging said sprocket to operate said impulse wheel to transmit impulses.

4:. In an impulse sender, the combination with an impulse transmitting mechanism and an endless chain for operating said mechanism, of a movable finger stop lever, and contact springs controlled by the movement of said lever.

In witness whereof, I hereunto subscribe my name this 14th day of July A. D., 1917.

OSCAR F. FORSBERG. 

